Multiple-thread monitor for bobbinbuilding mechanism and the like



June 18, 1968 E. HAMEL 3,388,544

MULTIPLE-THREAD MONITOR FOR BOBBIN-BUILDING MECHANISM AND THE LIKE Filed March 27, 1967 I! 4 O 24' O A \k 3 r 1.2 .27 13' so 12' 14 a Z 1L Q 28 i ll Edmund Hamel INVENTOR.

Attorney 8 Claims. ((51. s7-s1 ABSTRACT OF THE DISCLOSURE Device for simultaneously monitoring the tension in two or more threads delivered by separate feeders to a twisting station, e.g., preparatorily to the winding of the resulting yarn onto a bobbin, each feeder having associated with it a separate thread guard in the form of a biased switch arm engaging the respective thread; upon rupture of any thread, the corresponding switch arm shifts a common control member into an off-normal position to deactivate all the feeders and, preferably, to arrest the bobbin-winding mechanism. With at least one thread guard disposed between its feeder and the twisting station, a rupture of the twisted yarn will slacken the thread as sociated with that guard, thereby allowing the switch arm thereof to occupy its off-normal position.

My present invention relates to a device for simultaneously monitoring the tension in two or more threads delivered, as in a twisting or spinning machine, to a bobbin-building mechanism or similar station wherein several threads are combined into a yarn.

In the case of a simple twist, the component threads may be delivered at identical rates to the twisting station by a common feed mechanism which may have associated therewith a conventional thread guard designed to stop the feed and, advantageously, to arrest the drive for the bobbin spindle or other take-up device for the yarn in the case of a rupture. If, however, the threads are to be continuously or temporarily supplied at different rates, separate feeders are required and individual monitoring of the several threads becomes necessary along with, preferably, a supervision of the tension in the resulting yarn. Thus, conventional thread guards can no longer be used in installations of this type.

The general object of my invention, therefore, is to provide a monitoring device for bobbin-building mechanisms and the like which performs the individual supervision of the component threads in a simple manner and with a minimum duplication of parts.

An ancillary object is to provide means in such monitoring device for sensing an excessive slack, indicative of possible rupture, not only in the constituent threads but also in the resulting yarn.

In accordance with the present invention I provide, in a plant of the aforedescribed character, a control mem ber common to the several thread-feeding units for concurrently deactivating same upon displacement of this member from a normal to an off-normal position, the control member being engageable for such displacement by several thread guards individually assigned to the respective threads so as to be maintained thereby in an inactive position against a biasing force, tending to move the control member into its off-normal position, as long as the associated threads are under normal tension.

The biasing force may be supplied by gravity and/or springs acting upon the several thread guards which advantageously are in the form of bell-crank levers urged A United States Patent 3,388,544 Patented June 18, 1968 "ice by their own weight into engagement with respective abutments on a shiftable bar representing the aforementioned control member; the latter may be suspended, at or near its ends, from a pair of substantially vertical links defining therewith a parallelogrammatic linkage, the links themselves being provided with one-sided extensions loading the parallelogrammatic linkage for movement into its normal position in which the feeders are operative and the drive for the yarn take-up is energized. Each feeding unit may in this case comprise a pair of coacting rollers, including a driven roller and a counterroller, arranged to be separated from each other by one of the aforesaid link extensions.

In principle, the thread guards could be disposed for engagement with their respective threads either ahead of or behind the associated feeding unit. If at least one of these thread guards is positioned downstream from the respective feeding unit, i.e. between that unit and the twisting station, it will register a slackening not only of the corresponding thread but also of the twisted yarn so as to obviate the need for a separate thread guard to monitor the yarn tension.

The sole figure of the accompanying drawing illustrates, somewhat diagrammatically, a bobbin-building mechanism in combination with a multiple-thread monitor embodying my invention.

As shown in the drawing, two separate reels 2, 2 deliver a pair of threads 1, 1 to respective feeding units 4, 5 and 4, 5' which individually advance these threads, possibly at different rates, to a twisting station in which the threads are combined into a yarn 8 to be wound into a bobbin 11. Thread 1', after passing around a deflecting bar 7, joins the thread 1 in an eyelet 6 from which the yarn 8 advances to a traveler ring 10 which circles the axis of bobbin 11 on an annular track 9 reciprocating in the direction of the bobbin axis (arrow A) as is well known per se. The bobbin 11 has a core 21 mounted on a spindle 22 which is driven, via a transmission 23, from a motor 24 whose power supply has been diagrammatically indicated as a generator 25 in series with a pair of contacts 16. It will be understood that, in accordance with general practice, a multiplicity of bobbins 11 are built simultaneously on a bank of spindles 22 which are usually so closely spaced that, in the event of a rupture, a loose thread will become entangled with the yarn of a neighboring bobbin unless the affected spindle is promptly arrested.

In accordance with this invention I provide, for each of the threads 1 and 1', and individual thread guard shown to comprise a bell-crank lever 3, 3' pivoted at a respective fixed fulcrum 26, 26. By its own weight, and/ or by the action of a weak spring 27, 27 each lever 3, 3' is biased for swinging in a counterclockwise direction as indicated by arrows B, B. Such a swing, however, is normally prevented by the tension of the associated thread 1 or 1' which passes through a loop on the free end of the nearly horizontal bell-crank arm, thus holding the vertical arm against a respective stop 17, 17'. The vertical arms of levers 3 and 3 are disposed next to respective abutments 15 and 15 on a horizontal bar 14 which is suspended from links 28, 28'; these links are articulated to the bar 14 and have fixed fulcra at 29, 29' whose spacing substantially corresponds to the length of the bar so that a parallelogrammatic linkage is formed. Links 28, 23' are provided with integral extensions 12, 12 disposed unsymmetrically with reference to fulcra 29, 29 so as to tend to maintain the link 28 in contact with an abutment 30. Extensions 12 and 12 terminate in cams 13, 13 which, upon a counterclockwise swing thereof as indicated by arrows C, C, lift the respective counterrollers 5, 5' of the associated feeding unit from the corresponding driven rollers 4 and 4' to halt the drawing of further lengths of thread 1, 1' from reels 2, 2'. Bar 14, in its illustrated normal position in which cams 13 and 13' are Withdrawn from roilers 5 and 5', keeps closed the contacts 16 in the energizing circuit of motor 24'; naturally, this energizing circuit may include other switches, not shown, for starting and stopping the motor in the closed state of these contacts.

As long as the threads 1 and 1 are intact, elements 12 14 occupy their illustrated position and the system operates in the normal manner to build the bobbin 11. If, however, thread 1 is ruptured, lever 3 swings in the direction of arrow B and bears upon the abutment 15 to displace the bar 14 to the right, as indicated by arrow D, whereby contacts 16 are opened and motor 24 stops. At the same time the arms 13 and 13' lift up the counterrollers 5 and 5 which, in the embodiment illustrated, normally rest under their own weight on the associated driven rollers 4 and 4'. Both feeding units 4, 5 and 4, 5' are thereby deactivated even though rollers 4 and 4' may continue to rotate.

In an analogous manner, a rupture of thread 1' will cause the lever 25' to swing in the direction of arrow B to stop the motor 24 and to lift the two counterrollers 5 and 5'. Whereas, however, lever 3 engages the thread 1 ahead of feeder 4, 5 so as to respond instantly to any break in the thread between the reel 2 and the feeder, lever 3 is in contact with thread 1 at a downstream location from feeder 4, 5', between the latter and deflecting bar 7, whereby a break in thread 1 will become effective as soon as it clears the rollers 4, 5'; at the same time, any rupture in the yarn 8 will slacken the thread 1 so that thread guard 3 will react in the same manner as if this thread itself had been broken.

Naturally, the system described and illustrated may be extended for use with three or more threads by the provision of additional thread guards and lifting cams operatively coupled with the bar 14, or with an extension thereof, in the manner of levers 3, 3' and the links 28, 28' as explained above. These and other modifications apparent to persons skilled in the art are deemed to be embraced within the spirit and scope of my invention as defined in the appended claims.

I claim:

1. In a plant comprising a twisting station for a plurality of threads and individual feeding units for said threads, the combination therewith of a control member common to said feeding units for concurrently deactivating the latter upon a displacement of said member from a normal to an off-normal position, and a plurality of thread guards respectively positioned adjacent said feeding units for engagement with the threads thereof, each of said thread guards being biased for displacing said mem her into said off-normal position upon a rupture of the thread respectively associated therewith.

2. The combination defined in claim 1 wherein each of said thread guards comprises a swingable arm having an extremity engageable with said member.

3. The combination defined in claim 2 wherein said member comprises a generally horizontal bar and a pair of generally vertical links articulated to the ends of said bar for defining therewith a parallelogrammatic linkage, said bar being provided With abutments respectively engageable by the arms of said thread guards.

4. The combination defined in claim 3 wherein said links are provided with one-sided extensions tending to maintain said linkage by their own weight in its normal position.

5. The combination defined in claim 4 wherein said feeding units comprise each a driven roller and a counterroller, said extensions being engageable with said counterrollers for separating them from the corresponding driven rollers.

6. The combination defined in claim 3 wherein said arm is part of a bell-crank lever biased by its own weight into contact with a respective abutment of said bar.

7. The combination defined in claim 1 wherein at least one of said thread guards is disposed along a portion of thread lying between the respective feeding unit and said twisting station.

8. The combination defined in claim 1 wherein said twisting station includes a bobbin winder provided with drive means therefor, further comprising switch means operable by said control member in said off-normal position thereof for arresting said drive means.

References Cited UNITED STATES PATENTS 1,874,502 8/1932 Green 57-84 XR FOREIGN PATENTS 508,176 1/1952 Belgium.

FRANK I. COHEN, Primary Examiner. W. H. SCHROEDER, Assistant Examiner. 

